Dumbarton Oaks Gardens is closing for about 8 months starting July. So you really ought to plan a trip there soon before the gates close till next March.
Dumbarton Oaks in late May is not exactly at its peak in terms of blooms. The wisteria flowers are faded, the cherries and magnolias long gone, but the greenery is pretty great. And the peonies and roses are blooming.
Here’s how it’s looking this week: